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Finding the Fourth Proportional to 305.72, 457.68 and 208.40

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Solution

The fourth proportional to 305.72, 457.68 and 208.40 is: 311.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.72 : 457.68 = 208.40 : x
  2. Step 2: Convert to fraction form
    305.72/457.68 = 208.40/x
  3. Step 3: Cross multiply
    305.72x = 457.68 × 208.40
  4. Step 4: Simplify right side
    305.72x = 95,380.51
  5. Step 5: Solve for x
    x = 95,380.51/305.72
  6. Step 6: Final answer
    x = 311.99

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.